Oral administration of drugs is frequently affected by food-drug interactions, a phenomenon often described by the term “food effect”. As generally interpreted, food effect is a very broad term which refers to all aspects of interactions of food on drug dissolution, absorption, distribution, metabolism and elimination. The implications of food effect include changes in bioavailability, rate of on-set, duration of therapeutic effect and incidence and seriousness of side effects.
The food effect is an important issue during the development of a drug. In some cases where food-drug interactions lead to an increase of drug absorption, the drug formulation is recommended to be taken with food in order to be sufficiently absorbed and exert its expected clinical effect. However, such drug formulations are not preferred because drug absorption can vary with food types and quantity. For example, if a patient forgets to take the drug formulation with food, the drug may be poorly absorbed and therefore not clinically efficient. This problem may be avoided by a formulation without food effect.
Thus, there is a need for new sustained release compositions with reduced or no significant food effect.
Metformin is an oral antihyperglycemic drug of the biguanide class used in the management of non-insulin-dependent diabetes mellitus (NIDDM). It has been widely prescribed for lowering blood glucose in patients with NIDDM.
The benefits of a sustained release dosage form of metformin have been well known: it allows one to simplify the patient's administration scheme by reducing the amount of recommended daily intakes, improves patient compliance, and attenuates adverse events, e.g., related to high plasma peaks. Immediate release compositions of metformin exhibit negative food effect when orally administered to a subject.
The commercially available sustained-release dosage forms of metformin, such as Glucophage® XR, Glumetza® and Fortamet®, have significant positive food effect. Thus, they are all recommended to be taken with food to increase drug bioavailabiltiy and maximum therapeutic benefits.
Thus, there is a need for new sustained release compositions of metformin with reduced or no significant food effect.